The applicant has the broad career goal of improving the diagnostic evaluation, treatment recommendations, and health outcomes for patients with low back pain. In this project he proposes to extend his prior training in outcomes research, technology assessment, medical decision-making, and biostatistics. These advanced quantitative skills will be used to identify optimal treatment strategies for subgroups of low back pain patients defined on the basis of clinical and radiologic features. Low back pain is one of the most prevalent and costly health problems in the industrial world. Back surgery is nearly always elective, yet the rates of spine surgery in the US have increased dramatically in the past 10 years and show marked geographic variation. Both the First and Second International Forums for Primary Care Research on Low Back Pain chose the identification of important clinical subgroups of low back pain patients based on characteristics, imaging studies and other factors as their number one research priority. The data and infrastructure provided by the recently initiated Spine Patient Outcomes Research Trial (SPORT) presents a unique opportunity to study the predictors of outcome for patients with herniated discs, spinal stenosis, and degenerative spondylolisthesis. SPORT is a set of clinical trials designed to compare the effectiveness of surgical and non-surgical approaches to the treatment of these conditions; it is being conducted at I I U.S. medical centers and expects to enroll approximately 3000 patients. Extensive clinical, functional status, quality of life, and imaging data will allow for an unprecedented ability to identify optimal treatment approaches for these patients. This five-year project combines the use of outcomes research and decision analytic techniques to better understand the predictors of outcome with surgery and non-surgical treatment. After a period of additional training in decision in mdeling and biostatistics, the applicant will work closely with the Principal Investigator and Co-Principal vestigators of SPORT to accomplish two specific research objectives: To identify patient subgroups, defined by clinical and radiographic features at baseline, that are predictive of good/bad outcome with surgical/non-surgical treatment among patients with intervertebral disc herniation, spinal stenosis, or degenerative spondylolisthesis with associated stenosis. To develop decision analytic models for specific patient subgroups, which also accommodate individual patient preference and quality of life data, for the purpose of identifying optimal treatment strategies.